1. Field of the Invention
The present invention relates to an input apparatus or a communication terminal used for character entry.
2. Background Art
With the wide spreading use of portable telephones and other mobile terminals, such terminals are very actively employed for exchanging messages. And as is well known, senders use terminal input keys when entering character strings for messages. For this purpose, various input methods are presently provided. According to one example method, numeric keys 0 to 9, an asterisk key “*” and a pound key “#” are employed when entering or deleting kana (Japanese characters) or alphabet characters, as well as when entering other data. FIG. 14 is a diagram showing example characters and operations assigned by this method to the keys of a portable telephone terminal. For example, to input the kana character “ko”, numeric key “2” is depressed five times and the pound key is depressed to verify the entry. While for the character “M”, numeric key “6” is depressed 16 times, followed by the pound key.
Another character string input method is the technique, disclosed, for example, in Japanese Published Unexamined Patent Application (PUPA) No. Hei 6-6454, that is used as an input method for a pager, such as a so-called pocket bell (hereinafter referred to as a pager method). As is shown in FIG. 15, according to this technique a two-digit number is input to enter a character. For these numbers, the first digit (the tens digit) represents a consonant “row”, and the second digit (the units digit) represents a vowel “column”. For example, since the kana character “ko” is in the “k” row and the “o” column, its number is “25”, and to enter it, only key “2” and then key “5” are depressed. Therefore, two numbers consists one character.
However, with the conventional portable telephone terminal input method described above, the key “6” must be depressed 16 times to enter the alphabet character “M”, and a great deal of time and effort are required.
According to the pager method disclosed in Japanese Published Unexamined Patent Application (PUPA) No. Hei 6-6454, only two key depressions are required to enter a character, which is certainly an advantage. Furthermore, the regularity with which numbers are assigned for kana characters “a” to “wo” makes it easy to remember them. However, since that regularity does not apply to the kana character “n”, consonants and alphabet characters, the user must remember the numbers for these characters. Further, neither the portable telephone terminal method nor the pager method are very useful because each terminal maker arranges the input keys differently. In addition, although entering characters using a portable telephone terminal is frequently a one-handed-one-thumb operation, this can not be considered a superior process.
Furthermore, substantially, the conventional input method does not take usage by visually impaired persons into account. For while not merely a problem of the visually impaired, input errors tend to occur because so many movements of the thumb are required to manipulate the twelve input keys, “0” to “9”, “*” and “#”. Of course, since an input character appears on the display of a portable telephone terminal, an ordinary user can readily ascertain an entry error has been made, but no such means is available to assist a visually impaired person.
Recently, not only with personal computers but also with portable telephone terminals or other mobile terminals, it has become possible to use the Internet to obtain various services. But to avail one's self of a service, one must use a portable telephone terminal to access, through the Internet, the server that provides it, and must manipulate the portable telephone terminal in accordance with instructions that are received and displayed on a menu screen. However, since visually impaired persons can not see instructions received from servers when they are displayed on menu screens, they are effectively prevented from obtaining any services.
It is, therefore, one object of the present invention to provide an input apparatus, a communication terminal and a portable communication terminal that are eminently usable, especially by visually impaired persons when entering characters.
It is another object of the present invention to provide a speech feedback system, a speech feedback server and a communication terminal that can provide various services for visually impaired persons.